When to drain black tank?

[artgpo]

I have read in various RV publications and sites about not draining the black tanks until they are about 3/4 full. Since we are presently weekend campers we might only use the tanks for two days at a time. This rarely if ever results in a 3/4 full tank and since we have 1-1/2 baths we have two black tanks. Our new CF31QB has the black tank flush for each tank so I do vigorously flush after each draining. Am I going to get the dreaded residual dried up mess in the tank? Should I store the coach with "stuff" in the tanks until the next use?



Art

[croberts]

I think it depends - week to week you would be fine. Months? Not so much. I recommend putting 4-5 toilet fulls of water in the tank before each use. This gives you some water in there and keeps the chemicals and liquid form settling into the drain pipe. If I am going to dump the tank before it is full I usually put a lot of water ito the tank until it is 2/3 full. If I have a full hookup, I might do this twice.



With your tank flush, you could probably hook the flush up for a few minutes before pulling the handle, then dump, then flush some more. Obviously, I wouldn't do this at the dumo station making other wait.



I also put water back into the tank after dumping and add chemicals, so it is all ready to go for the next trip.

[geondebi]

I think there is truth to letting the tanks get full as I think it helps getting the big stuff out when dumping the tanks. But, I would not leave stuff in the tanks while in storage. I have seen posted when hooked up to a sewer system should the valve be left open and I would say no let it fill and drain at 3/4 or so. However, when leaving the camping area I do put about 2 or 3 gallons of water with soap to scrub the tanks on the way home and to keep a little water on the back side of the valve.

[mbinohio]

we do alot of 3 day trips and there is just 2 of us, I never leave a campground with anything but fresh water in my black tank, if you are half full, just fill it up and dump, always fill it before you dump..and why would you want to leave "stuff" in the tank ??...just fill it then dump it, flush it with your back flush and then I always put 4 toilet bowls full of water in the tank, and add your chemicals.........done, and nothing to worry about

[billyrabbit]

I've also heard that adding a bag of ice-cubes to the black tank before travelling either to or from your campsite is an effective way to ensure that you are not getting 'sludge' build up. You just need to add enough water to give the ice-cubes something to float in and they act as an effective abrasive as they slosh back and forthto break down solids.

[RanCar]

Originally Posted by billyrabbit

I've also heard that adding a bag of ice-cubes to the black tank before travelling either to or from your campsite is an effective way to ensure that you are not getting 'sludge' build up. You just need to add enough water to give the ice-cubes something to float in and they act as an effective abrasive as they slosh back and forthto break down solids.

Any chance that bag of melted cubes would get stuck on it's way out of the tank? I sure wouldn't want to put my hand down there to search for it.

[mbinohio]

wouldn't be a smart move to put the bag in, just dump the ice cubes, I use Calgon water softner in my black tank, a cup on every fill, makes the sides of the tank super slippery and nothing sticks to them, makes for a nice clean tank, Black tank matinance is not a hard or complicated thing, the most important thing is the tank needs to be full before you dump, we have camped for over 30yrs and never had a toilet problem.......

[fhenn]

We too do a lot of week end camping, I never leave the campgroung with any thing in the black tank. That's what they make the back flush for. Every 6 months or so I will put a bag of ice in the system.

[challeno]

It's best to wait til it's at least 3/4 full,,,I wait til my black water tank light says Full,,,,,the reason for this is so the waste doesn't dry on your walls and with a full tank you have alot of pressure that releases at once when you open your valve,,helping get more waste out,,,,before I leave the camp site I hook a flush wand up to a water hose and insert it in the tank from tolit side and spray the tank out,,,you can get a wand real cheap at any place that sells RV supplies,,,they work good ,,,then you don't have to worry about waste drying up on the side walls of the tank,,,it doesn't take ten mins.,,,,well,,that's my 2 cent...Edited by: challeno

[Hamops]

Occasionally, we'll leave a campsite without dumping the black tank and that's only because it was dumped the day before and it hasn't had much use. Normally, I dump it, flush it with the tank sprayer until it's relatively clean. Then I add about a cup of Calgon and use the tank sprayer to add about 5 gallons of water. This does two things; first it's one less thing I have to do at the next campsite andsecondly, it helps loosen any matter that may be in the tank by the sloshing action of the water caused my the movement of the trailer. When we layup the trailer for the winter, all the tanks are drained.

[oldblue]

I would not hook up the flush on tank and turn the water on with out opening valve. Sooneror later you will get busy and forget it . Seen it happen toafriend. Not a pretty site or smell

[sheltieRV]

Originally Posted by oldblue

I would not hook up the flush on tank and turn the water on with out opening valve. Sooneror later you will get busy and forget it . Seen it happen toafriend. Not a pretty site or smell

I got lucky this weekend. had the valve open and the flush on. Left to go for a walk, came back and the sewer hose had somehow slipped off the slinky and was no longer draining. Caught it before it filled up though.Edited by: sheltieRV

[Road King]

I want to be sure I have this right......

When you have a full hook up you let the tanks fill and then dump? You don't just keep the valve open and let everything go? And this is due to build up in the tank itself?

Remember, I am a little new to this.

Thanks in advance.

Dave

[mwebber78]

Exactly, the grey tanks don't really mater as much (my opinion).



You do NOT want to leave a black tank valve open or drain a partial tank. When open, liquid will leave the tank and all solids will make a nice mound under your toliet.

[Road King]

Thanks Mike!

Damn, I'm glad I joined this forum. You folks are a wealth of information!

Dave

[ClassicHammond]

Mike forgot to mention that the "pile" getshardbut will continue to smell. And there is less odor with a water suspension Check out the Calgon method of black tank maintainence. Many of us use it and are happy.